U.S. forces use small, high-speed boats for military purposes in coastal areas. These boats are typically about 30-70 feet long, and operate in a planning mode around 40 to 50 knots. Boats of similar size and mechanical specifications may also be used in the private sector for non-military purposes such as recreation. However, because of the size of the boats and the speed at which they travel, these craft experience high shock acceleration levels when traveling through waves, which results in injuries to passengers. Passengers may experience repetitive trauma resulting in acute injury to the lower back, knees, and neck.
At high sea states, craft accelerations in excess of 7 to 10 g's have been reported. Laboratory tests of slamming ship models show acceleration levels from 4 to 6 g's. It is therefore desired to reduce shock levels that these boats and their passengers experience. It is furthermore desired to incorporate a shock damping arrangement into the boat design.